diff options
Diffstat (limited to 'arch/um/os-Linux')
| -rw-r--r-- | arch/um/os-Linux/Makefile | 6 | ||||
| -rw-r--r-- | arch/um/os-Linux/elf_aux.c | 37 | ||||
| -rw-r--r-- | arch/um/os-Linux/internal.h | 13 | ||||
| -rw-r--r-- | arch/um/os-Linux/main.c | 6 | ||||
| -rw-r--r-- | arch/um/os-Linux/process.c | 20 | ||||
| -rw-r--r-- | arch/um/os-Linux/signal.c | 46 | ||||
| -rw-r--r-- | arch/um/os-Linux/skas/process.c | 46 | ||||
| -rw-r--r-- | arch/um/os-Linux/smp.c | 148 | ||||
| -rw-r--r-- | arch/um/os-Linux/start_up.c | 54 | ||||
| -rw-r--r-- | arch/um/os-Linux/time.c | 78 | ||||
| -rw-r--r-- | arch/um/os-Linux/user_syms.c | 6 |
11 files changed, 319 insertions, 141 deletions
diff --git a/arch/um/os-Linux/Makefile b/arch/um/os-Linux/Makefile index fae836713487..f8d672d570d9 100644 --- a/arch/um/os-Linux/Makefile +++ b/arch/um/os-Linux/Makefile @@ -6,7 +6,7 @@ # Don't instrument UML-specific code KCOV_INSTRUMENT := n -obj-y = execvp.o file.o helper.o irq.o main.o mem.o process.o \ +obj-y = elf_aux.o execvp.o file.o helper.o irq.o main.o mem.o process.o \ registers.o sigio.o signal.o start_up.o time.o tty.o \ umid.o user_syms.o util.o skas/ @@ -14,10 +14,10 @@ CFLAGS_signal.o += -Wframe-larger-than=4096 CFLAGS_main.o += -Wno-frame-larger-than -obj-$(CONFIG_ARCH_REUSE_HOST_VSYSCALL_AREA) += elf_aux.o +obj-$(CONFIG_SMP) += smp.o USER_OBJS := $(user-objs-y) elf_aux.o execvp.o file.o helper.o irq.o \ main.o mem.o process.o registers.o sigio.o signal.o start_up.o time.o \ - tty.o umid.o util.o + tty.o umid.o util.o smp.o include $(srctree)/arch/um/scripts/Makefile.rules diff --git a/arch/um/os-Linux/elf_aux.c b/arch/um/os-Linux/elf_aux.c index 0a0f91cf4d6d..72f416edf252 100644 --- a/arch/um/os-Linux/elf_aux.c +++ b/arch/um/os-Linux/elf_aux.c @@ -14,37 +14,26 @@ #include <elf_user.h> #include <mem_user.h> #include "internal.h" +#include <linux/swab.h> +#if __BITS_PER_LONG == 64 +typedef Elf64_auxv_t elf_auxv_t; +#else typedef Elf32_auxv_t elf_auxv_t; +#endif /* These are initialized very early in boot and never changed */ char * elf_aux_platform; -extern long elf_aux_hwcap; -unsigned long vsyscall_ehdr; -unsigned long vsyscall_end; -unsigned long __kernel_vsyscall; +long elf_aux_hwcap; __init void scan_elf_aux( char **envp) { - long page_size = 0; elf_auxv_t * auxv; while ( *envp++ != NULL) ; for ( auxv = (elf_auxv_t *)envp; auxv->a_type != AT_NULL; auxv++) { switch ( auxv->a_type ) { - case AT_SYSINFO: - __kernel_vsyscall = auxv->a_un.a_val; - /* See if the page is under TASK_SIZE */ - if (__kernel_vsyscall < (unsigned long) envp) - __kernel_vsyscall = 0; - break; - case AT_SYSINFO_EHDR: - vsyscall_ehdr = auxv->a_un.a_val; - /* See if the page is under TASK_SIZE */ - if (vsyscall_ehdr < (unsigned long) envp) - vsyscall_ehdr = 0; - break; case AT_HWCAP: elf_aux_hwcap = auxv->a_un.a_val; break; @@ -56,20 +45,6 @@ __init void scan_elf_aux( char **envp) elf_aux_platform = (char *) (long) auxv->a_un.a_val; break; - case AT_PAGESZ: - page_size = auxv->a_un.a_val; - break; } } - if ( ! __kernel_vsyscall || ! vsyscall_ehdr || - ! elf_aux_hwcap || ! elf_aux_platform || - ! page_size || (vsyscall_ehdr % page_size) ) { - __kernel_vsyscall = 0; - vsyscall_ehdr = 0; - elf_aux_hwcap = 0; - elf_aux_platform = "i586"; - } - else { - vsyscall_end = vsyscall_ehdr + page_size; - } } diff --git a/arch/um/os-Linux/internal.h b/arch/um/os-Linux/internal.h index 5d8d3b0817a9..bac9fcc8c14c 100644 --- a/arch/um/os-Linux/internal.h +++ b/arch/um/os-Linux/internal.h @@ -4,6 +4,7 @@ #include <mm_id.h> #include <stub-data.h> +#include <signal.h> /* * elf_aux.c @@ -16,8 +17,20 @@ void scan_elf_aux(char **envp); void check_tmpexec(void); /* + * signal.c + */ +extern __thread int signals_enabled; +int timer_alarm_pending(void); + +/* * skas/process.c */ void wait_stub_done(int pid); void wait_stub_done_seccomp(struct mm_id *mm_idp, int running, int wait_sigsys); + +/* + * smp.c + */ +#define IPI_SIGNAL SIGRTMIN + #endif /* __UM_OS_LINUX_INTERNAL_H */ diff --git a/arch/um/os-Linux/main.c b/arch/um/os-Linux/main.c index 3c63ce19e3bf..7e114862a723 100644 --- a/arch/um/os-Linux/main.c +++ b/arch/um/os-Linux/main.c @@ -21,8 +21,6 @@ #define STACKSIZE (8 * 1024 * 1024) -long elf_aux_hwcap; - static void __init set_stklim(void) { struct rlimit lim; @@ -149,9 +147,7 @@ int __init main(int argc, char **argv, char **envp) install_fatal_handler(SIGINT); install_fatal_handler(SIGTERM); -#ifdef CONFIG_ARCH_REUSE_HOST_VSYSCALL_AREA scan_elf_aux(envp); -#endif change_sig(SIGPIPE, 0); ret = linux_main(argc, argv, envp); @@ -171,7 +167,7 @@ int __init main(int argc, char **argv, char **envp) */ /* stop timers and set timer signal to be ignored */ - os_timer_disable(); + os_timer_disable(0); /* disable SIGIO for the fds and set SIGIO to be ignored */ err = deactivate_all_fds(); diff --git a/arch/um/os-Linux/process.c b/arch/um/os-Linux/process.c index 00b49e90d05f..3a2a84ab9325 100644 --- a/arch/um/os-Linux/process.c +++ b/arch/um/os-Linux/process.c @@ -10,6 +10,8 @@ #include <errno.h> #include <signal.h> #include <fcntl.h> +#include <limits.h> +#include <linux/futex.h> #include <sys/mman.h> #include <sys/ptrace.h> #include <sys/prctl.h> @@ -189,3 +191,21 @@ void os_set_pdeathsig(void) { prctl(PR_SET_PDEATHSIG, SIGKILL); } + +int os_futex_wait(void *uaddr, unsigned int val) +{ + int r; + + CATCH_EINTR(r = syscall(__NR_futex, uaddr, FUTEX_WAIT, val, + NULL, NULL, 0)); + return r < 0 ? -errno : r; +} + +int os_futex_wake(void *uaddr) +{ + int r; + + CATCH_EINTR(r = syscall(__NR_futex, uaddr, FUTEX_WAKE, INT_MAX, + NULL, NULL, 0)); + return r < 0 ? -errno : r; +} diff --git a/arch/um/os-Linux/signal.c b/arch/um/os-Linux/signal.c index 11f07f498270..327fb3c52fc7 100644 --- a/arch/um/os-Linux/signal.c +++ b/arch/um/os-Linux/signal.c @@ -20,6 +20,7 @@ #include <um_malloc.h> #include <sys/ucontext.h> #include <timetravel.h> +#include "internal.h" void (*sig_info[NSIG])(int, struct siginfo *, struct uml_pt_regs *, void *mc) = { [SIGTRAP] = relay_signal, @@ -68,12 +69,12 @@ static void sig_handler_common(int sig, struct siginfo *si, mcontext_t *mc) #define SIGCHLD_BIT 2 #define SIGCHLD_MASK (1 << SIGCHLD_BIT) -int signals_enabled; +__thread int signals_enabled; #if IS_ENABLED(CONFIG_UML_TIME_TRAVEL_SUPPORT) static int signals_blocked, signals_blocked_pending; #endif -static unsigned int signals_pending; -static unsigned int signals_active = 0; +static __thread unsigned int signals_pending; +static __thread unsigned int signals_active; static void sig_handler(int sig, struct siginfo *si, mcontext_t *mc) { @@ -159,6 +160,11 @@ void timer_set_signal_handler(void) set_handler(SIGALRM); } +int timer_alarm_pending(void) +{ + return !!(signals_pending & SIGALRM_MASK); +} + void set_sigstack(void *sig_stack, int size) { stack_t stack = { @@ -253,9 +259,29 @@ int change_sig(int signal, int on) return 0; } -void block_signals(void) +static inline void __block_signals(void) { + if (!signals_enabled) + return; + + os_local_ipi_disable(); + barrier(); signals_enabled = 0; +} + +static inline void __unblock_signals(void) +{ + if (signals_enabled) + return; + + signals_enabled = 1; + barrier(); + os_local_ipi_enable(); +} + +void block_signals(void) +{ + __block_signals(); /* * This must return with signals disabled, so this barrier * ensures that writes are flushed out before the return. @@ -272,7 +298,8 @@ void unblock_signals(void) if (signals_enabled == 1) return; - signals_enabled = 1; + __unblock_signals(); + #if IS_ENABLED(CONFIG_UML_TIME_TRAVEL_SUPPORT) deliver_time_travel_irqs(); #endif @@ -306,7 +333,7 @@ void unblock_signals(void) * tracing that happens inside the handlers we call for the * pending signals will mess up the tracing state. */ - signals_enabled = 0; + __block_signals(); um_trace_signals_off(); /* @@ -338,10 +365,15 @@ void unblock_signals(void) /* Re-enable signals and trace that we're doing so. */ um_trace_signals_on(); - signals_enabled = 1; + __unblock_signals(); } } +int um_get_signals(void) +{ + return signals_enabled; +} + int um_set_signals(int enable) { int ret; diff --git a/arch/um/os-Linux/skas/process.c b/arch/um/os-Linux/skas/process.c index 0bc10cd4cbed..d6c22f8aa06d 100644 --- a/arch/um/os-Linux/skas/process.c +++ b/arch/um/os-Linux/skas/process.c @@ -298,7 +298,6 @@ static int userspace_tramp(void *data) .seccomp = using_seccomp, .stub_start = STUB_START, }; - struct iomem_region *iomem; int ret; if (using_seccomp) { @@ -332,12 +331,6 @@ static int userspace_tramp(void *data) fcntl(init_data.stub_data_fd, F_SETFD, 0); - /* In SECCOMP mode, these FDs are passed when needed */ - if (!using_seccomp) { - for (iomem = iomem_regions; iomem; iomem = iomem->next) - fcntl(iomem->fd, F_SETFD, 0); - } - /* dup2 signaling FD/socket to STDIN */ if (dup2(tramp_data->sockpair[0], 0) < 0) exit(3); @@ -553,7 +546,7 @@ extern unsigned long tt_extra_sched_jiffies; void userspace(struct uml_pt_regs *regs) { int err, status, op; - siginfo_t si_ptrace; + siginfo_t si_local; siginfo_t *si; int sig; @@ -564,6 +557,13 @@ void userspace(struct uml_pt_regs *regs) struct mm_id *mm_id = current_mm_id(); /* + * At any given time, only one CPU thread can enter the + * turnstile to operate on the same stub process, including + * executing stub system calls (mmap and munmap). + */ + enter_turnstile(mm_id); + + /* * When we are in time-travel mode, userspace can theoretically * do a *lot* of work without being scheduled. The problem with * this is that it will prevent kernel bookkeeping (primarily @@ -630,9 +630,10 @@ void userspace(struct uml_pt_regs *regs) } if (proc_data->si_offset > sizeof(proc_data->sigstack) - sizeof(*si)) - panic("%s - Invalid siginfo offset from child", - __func__); - si = (void *)&proc_data->sigstack[proc_data->si_offset]; + panic("%s - Invalid siginfo offset from child", __func__); + + si = &si_local; + memcpy(si, &proc_data->sigstack[proc_data->si_offset], sizeof(*si)); regs->is_user = 1; @@ -728,8 +729,8 @@ void userspace(struct uml_pt_regs *regs) case SIGFPE: case SIGWINCH: ptrace(PTRACE_GETSIGINFO, pid, 0, - (struct siginfo *)&si_ptrace); - si = &si_ptrace; + (struct siginfo *)&si_local); + si = &si_local; break; default: si = NULL; @@ -740,6 +741,8 @@ void userspace(struct uml_pt_regs *regs) } } + exit_turnstile(mm_id); + UPT_SYSCALL_NR(regs) = -1; /* Assume: It's not a syscall */ if (sig) { @@ -809,10 +812,9 @@ void switch_threads(jmp_buf *me, jmp_buf *you) static jmp_buf initial_jmpbuf; -/* XXX Make these percpu */ -static void (*cb_proc)(void *arg); -static void *cb_arg; -static jmp_buf *cb_back; +static __thread void (*cb_proc)(void *arg); +static __thread void *cb_arg; +static __thread jmp_buf *cb_back; int start_idle_thread(void *stack, jmp_buf *switch_buf) { @@ -866,10 +868,10 @@ void initial_thread_cb_skas(void (*proc)(void *), void *arg) cb_arg = arg; cb_back = &here; - block_signals_trace(); + initial_jmpbuf_lock(); if (UML_SETJMP(&here) == 0) UML_LONGJMP(&initial_jmpbuf, INIT_JMP_CALLBACK); - unblock_signals_trace(); + initial_jmpbuf_unlock(); cb_proc = NULL; cb_arg = NULL; @@ -878,8 +880,9 @@ void initial_thread_cb_skas(void (*proc)(void *), void *arg) void halt_skas(void) { - block_signals_trace(); + initial_jmpbuf_lock(); UML_LONGJMP(&initial_jmpbuf, INIT_JMP_HALT); + /* unreachable */ } static bool noreboot; @@ -899,6 +902,7 @@ __uml_setup("noreboot", noreboot_cmd_param, void reboot_skas(void) { - block_signals_trace(); + initial_jmpbuf_lock(); UML_LONGJMP(&initial_jmpbuf, noreboot ? INIT_JMP_HALT : INIT_JMP_REBOOT); + /* unreachable */ } diff --git a/arch/um/os-Linux/smp.c b/arch/um/os-Linux/smp.c new file mode 100644 index 000000000000..18d3858a7cd2 --- /dev/null +++ b/arch/um/os-Linux/smp.c @@ -0,0 +1,148 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2025 Ant Group + * Author: Tiwei Bie <tiwei.btw@antgroup.com> + */ + +#include <errno.h> +#include <pthread.h> +#include <signal.h> +#include <kern_util.h> +#include <um_malloc.h> +#include <init.h> +#include <os.h> +#include <smp.h> +#include "internal.h" + +struct cpu_thread_data { + int cpu; + sigset_t sigset; +}; + +static __thread int __curr_cpu; + +int uml_curr_cpu(void) +{ + return __curr_cpu; +} + +static pthread_t cpu_threads[CONFIG_NR_CPUS]; + +static void *cpu_thread(void *arg) +{ + struct cpu_thread_data *data = arg; + + __curr_cpu = data->cpu; + + uml_start_secondary(data); + + return NULL; +} + +int os_start_cpu_thread(int cpu) +{ + struct cpu_thread_data *data; + sigset_t sigset, oset; + int err; + + data = uml_kmalloc(sizeof(*data), UM_GFP_ATOMIC); + if (!data) + return -ENOMEM; + + sigfillset(&sigset); + if (sigprocmask(SIG_SETMASK, &sigset, &oset) < 0) { + err = errno; + goto err; + } + + data->cpu = cpu; + data->sigset = oset; + + err = pthread_create(&cpu_threads[cpu], NULL, cpu_thread, data); + if (sigprocmask(SIG_SETMASK, &oset, NULL) < 0) + panic("Failed to restore the signal mask, errno = %d", errno); + if (err != 0) + goto err; + + return 0; + +err: + kfree(data); + return -err; +} + +void os_start_secondary(void *arg, jmp_buf *switch_buf) +{ + struct cpu_thread_data *data = arg; + + sigaddset(&data->sigset, IPI_SIGNAL); + sigaddset(&data->sigset, SIGIO); + + if (sigprocmask(SIG_SETMASK, &data->sigset, NULL) < 0) + panic("Failed to restore the signal mask, errno = %d", errno); + + kfree(data); + longjmp(*switch_buf, 1); + + /* unreachable */ + printk(UM_KERN_ERR "impossible long jump!"); + fatal_sigsegv(); +} + +int os_send_ipi(int cpu, int vector) +{ + union sigval value = { .sival_int = vector }; + + return pthread_sigqueue(cpu_threads[cpu], IPI_SIGNAL, value); +} + +static void __local_ipi_set(int enable) +{ + sigset_t sigset; + + sigemptyset(&sigset); + sigaddset(&sigset, IPI_SIGNAL); + + if (sigprocmask(enable ? SIG_UNBLOCK : SIG_BLOCK, &sigset, NULL) < 0) + panic("%s: sigprocmask failed, errno = %d", __func__, errno); +} + +void os_local_ipi_enable(void) +{ + __local_ipi_set(1); +} + +void os_local_ipi_disable(void) +{ + __local_ipi_set(0); +} + +static void ipi_sig_handler(int sig, siginfo_t *si, void *uc) +{ + int save_errno = errno; + + signals_enabled = 0; + um_trace_signals_off(); + + uml_ipi_handler(si->si_value.sival_int); + + um_trace_signals_on(); + signals_enabled = 1; + + errno = save_errno; +} + +void __init os_init_smp(void) +{ + struct sigaction action = { + .sa_sigaction = ipi_sig_handler, + .sa_flags = SA_SIGINFO | SA_ONSTACK | SA_RESTART, + }; + + sigfillset(&action.sa_mask); + + if (sigaction(IPI_SIGNAL, &action, NULL) < 0) + panic("%s: sigaction failed, errno = %d", __func__, errno); + + cpu_threads[0] = pthread_self(); +} diff --git a/arch/um/os-Linux/start_up.c b/arch/um/os-Linux/start_up.c index a827c2e01aa5..054ac03bbf5e 100644 --- a/arch/um/os-Linux/start_up.c +++ b/arch/um/os-Linux/start_up.c @@ -22,6 +22,7 @@ #include <asm/unistd.h> #include <init.h> #include <os.h> +#include <smp.h> #include <kern_util.h> #include <mem_user.h> #include <ptrace_user.h> @@ -481,6 +482,9 @@ void __init os_early_checks(void) fatal("SECCOMP userspace requested but not functional!\n"); } + if (uml_ncpus > 1) + fatal("SMP is not supported with PTRACE userspace.\n"); + using_seccomp = 0; check_ptrace(); @@ -489,53 +493,3 @@ void __init os_early_checks(void) fatal("Failed to initialize default registers"); stop_ptraced_child(pid, 1); } - -int __init parse_iomem(char *str, int *add) -{ - struct iomem_region *new; - struct stat64 buf; - char *file, *driver; - int fd, size; - - driver = str; - file = strchr(str,','); - if (file == NULL) { - os_warn("parse_iomem : failed to parse iomem\n"); - goto out; - } - *file = '\0'; - file++; - fd = open(file, O_RDWR, 0); - if (fd < 0) { - perror("parse_iomem - Couldn't open io file"); - goto out; - } - - if (fstat64(fd, &buf) < 0) { - perror("parse_iomem - cannot stat_fd file"); - goto out_close; - } - - new = malloc(sizeof(*new)); - if (new == NULL) { - perror("Couldn't allocate iomem_region struct"); - goto out_close; - } - - size = (buf.st_size + UM_KERN_PAGE_SIZE) & ~(UM_KERN_PAGE_SIZE - 1); - - *new = ((struct iomem_region) { .next = iomem_regions, - .driver = driver, - .fd = fd, - .size = size, - .phys = 0, - .virt = 0 }); - iomem_regions = new; - iomem_size += new->size + UM_KERN_PAGE_SIZE; - - return 0; - out_close: - close(fd); - out: - return 1; -} diff --git a/arch/um/os-Linux/time.c b/arch/um/os-Linux/time.c index 4d5591d96d8c..13ebc86918d4 100644 --- a/arch/um/os-Linux/time.c +++ b/arch/um/os-Linux/time.c @@ -11,12 +11,15 @@ #include <errno.h> #include <signal.h> #include <time.h> +#include <sys/signalfd.h> #include <sys/time.h> #include <kern_util.h> #include <os.h> +#include <smp.h> #include <string.h> +#include "internal.h" -static timer_t event_high_res_timer = 0; +static timer_t event_high_res_timer[CONFIG_NR_CPUS] = { 0 }; static inline long long timespec_to_ns(const struct timespec *ts) { @@ -31,20 +34,31 @@ long long os_persistent_clock_emulation(void) return timespec_to_ns(&realtime_tp); } +#ifndef sigev_notify_thread_id +#define sigev_notify_thread_id _sigev_un._tid +#endif + /** * os_timer_create() - create an new posix (interval) timer */ int os_timer_create(void) { - timer_t *t = &event_high_res_timer; + int cpu = uml_curr_cpu(); + timer_t *t = &event_high_res_timer[cpu]; + struct sigevent sev = { + .sigev_notify = SIGEV_THREAD_ID, + .sigev_signo = SIGALRM, + .sigev_value.sival_ptr = t, + .sigev_notify_thread_id = gettid(), + }; - if (timer_create(CLOCK_MONOTONIC, NULL, t) == -1) + if (timer_create(CLOCK_MONOTONIC, &sev, t) == -1) return -1; return 0; } -int os_timer_set_interval(unsigned long long nsecs) +int os_timer_set_interval(int cpu, unsigned long long nsecs) { struct itimerspec its; @@ -54,13 +68,13 @@ int os_timer_set_interval(unsigned long long nsecs) its.it_interval.tv_sec = nsecs / UM_NSEC_PER_SEC; its.it_interval.tv_nsec = nsecs % UM_NSEC_PER_SEC; - if (timer_settime(event_high_res_timer, 0, &its, NULL) == -1) + if (timer_settime(event_high_res_timer[cpu], 0, &its, NULL) == -1) return -errno; return 0; } -int os_timer_one_shot(unsigned long long nsecs) +int os_timer_one_shot(int cpu, unsigned long long nsecs) { struct itimerspec its = { .it_value.tv_sec = nsecs / UM_NSEC_PER_SEC, @@ -70,19 +84,20 @@ int os_timer_one_shot(unsigned long long nsecs) .it_interval.tv_nsec = 0, // we cheat here }; - timer_settime(event_high_res_timer, 0, &its, NULL); + timer_settime(event_high_res_timer[cpu], 0, &its, NULL); return 0; } /** * os_timer_disable() - disable the posix (interval) timer + * @cpu: the CPU for which the timer is to be disabled */ -void os_timer_disable(void) +void os_timer_disable(int cpu) { struct itimerspec its; memset(&its, 0, sizeof(struct itimerspec)); - timer_settime(event_high_res_timer, 0, &its, NULL); + timer_settime(event_high_res_timer[cpu], 0, &its, NULL); } long long os_nsecs(void) @@ -93,23 +108,50 @@ long long os_nsecs(void) return timespec_to_ns(&ts); } +static __thread int wake_signals; + +void os_idle_prepare(void) +{ + sigset_t set; + + sigemptyset(&set); + sigaddset(&set, SIGALRM); + sigaddset(&set, IPI_SIGNAL); + + /* + * We need to use signalfd rather than sigsuspend in idle sleep + * because the IPI signal is a real-time signal that carries data, + * and unlike handling SIGALRM, we cannot simply flag it in + * signals_pending. + */ + wake_signals = signalfd(-1, &set, SFD_CLOEXEC); + if (wake_signals < 0) + panic("Failed to create signal FD, errno = %d", errno); +} + /** * os_idle_sleep() - sleep until interrupted */ void os_idle_sleep(void) { - struct itimerspec its; - sigset_t set, old; + sigset_t set; - /* block SIGALRM while we analyze the timer state */ + /* + * Block SIGALRM while performing the need_resched check. + * Note that, because IRQs are disabled, the IPI signal is + * already blocked. + */ sigemptyset(&set); sigaddset(&set, SIGALRM); - sigprocmask(SIG_BLOCK, &set, &old); + sigprocmask(SIG_BLOCK, &set, NULL); + + /* + * Because disabling IRQs does not block SIGALRM, it is also + * necessary to check for any pending timer alarms. + */ + if (!uml_need_resched() && !timer_alarm_pending()) + os_poll(1, &wake_signals); - /* check the timer, and if it'll fire then wait for it */ - timer_gettime(event_high_res_timer, &its); - if (its.it_value.tv_sec || its.it_value.tv_nsec) - sigsuspend(&old); - /* either way, restore the signal mask */ + /* Restore the signal mask. */ sigprocmask(SIG_UNBLOCK, &set, NULL); } diff --git a/arch/um/os-Linux/user_syms.c b/arch/um/os-Linux/user_syms.c index a310ae27b479..67f6112318b6 100644 --- a/arch/um/os-Linux/user_syms.c +++ b/arch/um/os-Linux/user_syms.c @@ -31,12 +31,6 @@ extern void *memset(void *, int, size_t); EXPORT_SYMBOL(memset); #endif -#ifdef CONFIG_ARCH_REUSE_HOST_VSYSCALL_AREA -/* needed for __access_ok() */ -EXPORT_SYMBOL(vsyscall_ehdr); -EXPORT_SYMBOL(vsyscall_end); -#endif - #ifdef _FORTIFY_SOURCE extern int __sprintf_chk(char *str, int flag, size_t len, const char *format); EXPORT_SYMBOL(__sprintf_chk); |